Mr. Cronenberg, the acclaimed film director (“Dead Ringers,” “A History of Violence”) says he doesn’t like returning to previously trodden creative ground. But he’s breaking his rule in a big way with a new Los Angeles Opera production based on his 1986 science-fiction horror film.

“The Fly,” with a score by three-time Oscar winner Mr. Shore (“The Lord of the Rings”) is the opera debut for both Mr. Cronenberg and Mr. Shore, who wrote the music for the film.

Also onboard are librettist David Henry Hwang (Tony-winning author of “M. Butterfly”), Oscar-winning production designer Dante Ferretti (“Sweeney Todd: The Demon Barber of Fleet Street”) and L.A. Opera Artistic Director Placido Do mingo, who will conduct and has helped bring new operas to Los Angeles before - such as the Julie Taymor-Elliot Goldenthal collaboration “Grendel.”

Commissioned in 2005 by Mr. Domingo for the L.A. Opera, the seven-performance run of “The Fly” begins Sunday at the Dorothy Chandler Pavilion after an early-summer engagement at the Theatre du Chatelet in Paris.

The Paris notices were mixed. Leads Daniel Okulitch and Ruxandra Donose earned praise, but French critics took a few swats at the piece as a whole.

It “confirmed that cinema and theater, above all opera, are two very different arts,” sniffed Le Figaro, while Le Monde concluded that the work “doesn’t fly.”

However, Mr. Cronenberg - who says he isn’t about to hang up his camera for this new medium - is undeterred, noting that the experience has been a joyful romp through a new toolbox.

“It was a massive learning experience,” the 65-year-old director says. “Once you accept that you’re doing stage more than embracing it dully, there are many things you get that you can’t do in film.”

Unlike Mr. Shore - an avid operagoer who says elements of opera have been working their way into the scores of films such as “Dead Ringers,” “Se7en” and “The Silence of the Lambs” - friend and fellow Canadian Mr. Cronenberg isn’t much for attending opera or the live stage.

“That’s no knock on stage,” Mr. Cronenberg says. “I don’t go to the cinemas much either.”

Nonetheless, through the years after the release of the film, Mr. Cronenberg and Mr. Shore would spitball ideas of how to bring “The Fly” to a new medium. The story’s structure - a love triangle largely within the same set - had Mr. Cronenberg thinking about staging “The Fly” as a play.

Mr. Shore, who would adapt his “Lord of the Rings” score into a choral piece, had other ideas.

“It wasn’t until I was writing ‘Lord of the Rings,’ which took me almost four years to write, that I felt ready to work on ‘The Fly,’” the 61-year-old composer says. “I was working my way up to it.”

“Ultimately, we came to an understanding,” Mr. Cronenberg says. “Mine was to say if we were going to do an opera, I really want to do it for the stage. I’m not interested in doing video projections, which is what a lot of people are doing these days, because that would be too much like remaking the movie.”

As in the film, “The Fly” concerns the doomed romance between eccentric scientist Seth Brundle and Veronica Quaife, his journalist lover. Stathis Borans, Veronica’s editor, is also her former lover.

Seth’s experiments in the teleportation of live matter go awry when a fly gets into the teleportation pod and fuses with the scientist’s DNA. He is gradually transformed into a grotesque human-insect mutation. Adding to the horror, Veronica realizes she is carrying Seth’s baby.

For the opera, both Canadian bass baritone Mr. Okulitch and Romanian mezzo-soprano Miss Donose are making their L.A. Opera debuts for the roles of Seth and Veronica, which were played in the film by then real-life couple Jeff Goldblum and Geena Davis.

Mr. Cronenberg’s 1986 screenplay was an adaptation of the same George Langelaan short story that also served as the basis for the 1958 film “The Fly,” starring Vincent Price. Unlike the cult black-and-white B-film, however, Mr. Cronenberg’s version had some nasty, colorful effects.

If exploding animals and maggot babies don’t strike you as opera fodder, you’re not the first person to be skeptical.

“The notion seemed sort of outrageous and right at the same time,” librettist Mr. Hwang admits. “One doesn’t normally think of operas based on science-fiction source material.

“But the way David has interpreted the material, it has a tragic love story, death and birth, transformation and a lot of things that make a good dramatic opera plot.”

Neither Mr. Cronenberg’s script nor Mr. Langelaan’s story were required research for creators or company members. Indeed, Mr. Hwang was encouraged to depart from what had been done previously. Mr. Shore says he barely even references his original score.

“One of the wonderful things about opera is that it’s a living art,” Mr. Shore says. “Sitting there every night, studying the pacing and making corrections and adjustments, is an ongoing process and a very complicated thing to do.”

Mr. Hwang, who adapted his play “M. Butterfly” for the film Mr. Cronenberg directed, placed the action in the 1950s and used the flashback structure of the original short story. He also borrowed elements from other of Mr. Cronenberg’s films.

The film won an Oscar for its (mostly grisly) makeup. Stephan L. Dupuis, another longtime Cronenberg collaborator, is handling makeup and creature design for the opera along with the team at Mark Rappaport’s Creature Effects.

The creative team behind the opera promises that certain special effects will make it to the stage, so the ick factor isn’t going away entirely.

“You can’t translate Brundle throwing up on Stathis’ foot and having it dissolve,” Mr. Hwang says, “but through a combination of costumes and effects that David has put in and the eeriness of the music, I think the opera gets quite disturbing in the second act.”